This invention relates to a system of humidifying air. More specifically, this invention relates to a system of humidifying air with a gas fired humidifier.
The need for a controlled supply of humidified air in medical and other applications is well documented. For example, a controlled supply of humidified air is needed to maintain a clean room in a hospital. Temperature, air pressure, and humidity conditions must be maintained precisely to maintain a pristine clean room. Problems associated with excessively dry air are well documented. The need to provide and maintain clean rooms is well known in the medical profession. Similarly, the importance of clean rooms is known to be critical in semiconductor chip fabrication operations as well as in the manufacture of other products.
Relatively small electric humidifiers are sometimes used in various building locations to provide the required humidity for clean rooms, etc. . . . Electric humidifiers generally employ an electric heating element for producing steam from a body of water. The steam is added to the building air supply to add water vapor to the air, thereby raising the humidity. It is also known to use relatively small gas fired humidifiers to provide humidity to selected areas of a building. One example of a known gas fired humidifier is described in U.S. Pat. No. 5,816,496 to Kovacs (hereinafter Kovacs). Kovacs discloses a stand-alone gas fired humidifier. These relatively small steam generating units are advantageous in not requiring long steam piping runs from a central source of building steam.
Typically, building humidification systems are centrally located large scale units which generate large quantities of steam to humidify various portions of the building. These large scale units are typically positioned at locations which are remote from the areas of the building to be humidified. Air ducts and other pipes are required to carry the steam or water vapor from the remote locations to the area to be humidified. Humidity detectors are generally used with humidifiers to modulate the amount of steam being produced.
When large scale humidification systems are employed, they lack the delicate controls that can be required to maintain the proper humidity in a relatively small area, such as a clean room. It would thus be desirable to provide a more efficient and more precisely controlled system for humidifying air with a gas fired humidifier.
The above objects as well as other objects not specifically enumerated are achieved by a system for providing humidified air. The system includes a tank containing water and one or more heat exchanger tubes mounted in the tank. The system includes a burner assembly positioned to supply heat to the heat exchanger tubes. The system includes an induction fan for inducing combustion gases from the burner assembly through the heat exchanger tubes. Heat from the burner assembly in he heat exchanger tubes generates steam in the tank. The system includes a steam dispersion apparatus connected to the tank for humidifying air with the steam and a means for measuring humidity in a target location. The system also includes a controller for controlling one or both of the fuel supply to the burner assembly or the induction fan in response to the measured humidity in the target location. According to this invention there is also provided a system for providing humidified air in a building. The system includes a tank containing water and one or re heat exchanger tubes mounted in the tank. The system includes a burner assembly positioned to supply heat to the heat exchanger tubes. The system includes an induction fan for inducing combustion gases from the burner assembly through the heat exchanger tubes. Heat from the burner assembly in the heat exchanger tubes generates steam in the tank. The system includes a steam dispersion apparatus connected to the tank for humidifying building air with the steam and a means for measuring humidity in a target location in the building. The system also includes a controller for controlling one or both of the fuel supply to the burner assembly or the induction fan in response to the measured humidity in the target location.
According to this invention there is also provided a method for controlling an air humidification process in a building. The method includes measuring the amount of humidity in a target location. The method includes providing fuel to one or more burner assemblies wherein the fuel is provided at a rate that varies within a range, and burning the fuel to generate combustion gases. The method also includes drawing the combustion gases with an induction fan from the one or more burner assemblies through a plurality of heat exchanger tubes to generate steam. The heat exchanger tubes are mounted in a tank containing water. The method also includes humidifying building air with the steam using a steam dispersion apparatus and controlling one or both of the fuel supply to the burner and the induction fan in response to the measured humidity in the target location.
According to this invention there is also provided a method for controlling an air humidification process. The method includes measuring the amount of humidity in a target location. The method includes providing fuel to one or more burner assemblies wherein the fuel is provided at a rate that varies within a range, and burning the fuel to generate combustion gases. The method also includes drawing the combustion gases with an induction fan from the one or more burner assemblies through a plurality of heat exchanger tubes to generate steam. The heat exchanger tubes are mounted in a tank containing water. The method also includes humidifying air with the steam using a steam dispersion apparatus and controlling one or both of the fuel supply to the burner and the induction fan in response to the measured humidity in the target location.
Various objects and advantages of this invention will become apparent to those skilled in the art from the following detailed description of the preferred embodiment, when read in light of the accompanying drawings.